The present invention minimizes or overcomes several problems associated with previous point-of-use home or office water treatment system (WTS) units. A first problem is that conventional WTS units, utilizing lamp assemblies with UV bulb assemblies therein, are energy inefficient. When a conventional lamp assembly is turned on, it takes a significant amount of start-up time before gases within a UV bulb assembly are sufficiently excited to output light of an intensity level required to insure adequate destruction of microorganisms within the WTS unit. Water which is discharged from the WTS unit before a UV bulb assembly is sufficiently excited and microorganisms properly irradiated may carry an unacceptably high level of live microorganisms. Consequently, conventional lamp assemblies are left continuously running which uses a significant amount of energy. Also, with the lamp assembly left running continuously, such as overnight, water residing within a WTS unit can become uncomfortably warm. Finally, the life expectancy of a lamp assembly which is kept running continuously is significantly reduced relative to a lamp assembly which is only activated when water is to be treated.
A second problem is with the design of reflector assemblies within WTS units. In an attempt to increase lamp efficiency, reflector assemblies may be placed about UV bulb assemblies and water carrying conduits in which the microorganisms are irradiated. Light emitted from a UV bulb assembly which misses striking water carrying conduits is reflected back from the reflectors walls and has a chance to again impinge upon the water carrying conduits. These reflector assemblies may be circular in cross-section. Unfortunately, a lot of the UV light produced by these circular reflector designs never reaches the water carrying conduits. Rather, a significant portion of reflected light is reabsorbed by the UV bulb assembly and never reaches the water carrying conduit.
A third problem involves the electrical coupling of the lamp assemblies to WTS units. Every time a lamp assembly is installed in or removed from a WTS unit, the lamp assembly must be mechanically and electrically coupled and uncoupled relative to the WTS unit. This often required complicated and expensive electrical mounting assemblies. Further, care must be taken to insure that the electrical connections are not exposed to moisture while electrical power is passing through the WTS unit.
Coaxially aligned lamp assemblies and filter assemblies are sometime used to minimize the size of WTS units. A lamp assembly and filter assembly in a particular WTS may or may not be simultaneously removed from the WTS unit. If these assemblies are simultaneously removed, they are often very quite heavy as they may have substantial weight on their own and may be filled with water. Alternatively, even if the lamp and filter assemblies are separably removably from a WTS unit, quite often problems exist of water spilling from one of these assemblies during handling.
Another problem faced by WTS units having UV lamp assemblies is that complicated monitoring systems are needed to monitor the lamp assemblies. As a lamp assembly ages, the intensity of UV light output from the lamp assembly generally diminishes. Eventually, the intensity falls below a level necessary to effect a desired microorganism kill rate. The lamp assembly should be replaced before the desired minimum intensity is reached. Accordingly, a monitoring system is required to check on the UV light intensity within the WTS unit. These monitoring systems are typically expensive. They often require costly UV light sensors with quartz windows.
Point-of-use water treatment systems are typically left running continuously due to microorganism growth that would otherwise occur if the systems were shut down. Lamp assemblies in typical WTS units require a relative long time to reach a threshold value of emitted radiation intensity needed to attain a desired kill rate. Accordingly, water containing unacceptably high levels of live microorganisms may be delivered from a WTS unit before that threshold value of light intensity is reached.
Other problems and deficiencies that typical WTS units have include complicated assembly and locking mechanisms for mounting filter and lamp assemblies which may include nuts, bolts and O-rings which must be manually installed.
These and other deficiencies in prior WTS units employing lamp assemblies and filter assemblies are overcome by the present invention.